Conventionally, the example of this kind of device includes a so-called “glasses type” stereoscopic image display device. Specifically, for example, the stereoscopic image display device includes a semi-transparent mirror and an image display unit having a pair of a first image display part and a second image display part, which are arranged to form an L-shape. The first image display part directly faces the viewer, and the second image display part is located on a position perpendicular to a screen of the first image display part. The semi-transparent mirror is provided from the corner portion of the image display unit in an inclined manner (see, for example, Patent Document 1).
In this “glasses type” stereoscopic image display device, for example, the first image display part displays a left-eye image, and the second image display part displays a right-eye image. The first image display part emits light, a part of which is reflected by the semi-transparent mirror, and the rest of which passes through the semi-transparent mirror toward the viewer. Part of the light emitted from the second image display part passes through the semi-transparent mirror, and the rest of the light is reflected and travels toward the viewer. Since the light reflected by the semi-transparent mirror has a polarization state different from that of the passing-through light, the viewer is capable of viewing the different images with left and right eyes when the viewer wears glasses having different polarizing characteristics on left and right visions. As a result, the viewer is capable of viewing the stereoscopic image.
Also, the other example of the device includes a so-called “naked-eye type” stereoscopic image display device. Specifically, the stereoscopic image display device includes, for example, an image display unit and a semi-transparent mirror. The image display unit includes a pair of image display parts arranged to form an L-shape. One of the image display parts includes a first image display part, which has a screen facing the viewer, and a first view field selective glass, which limits a view angle. The other one of the image display parts includes a second image display part, which is positioned perpendicularly to the screen of the first image display part, and a second view field selective glass, which limits a view angle. The semi-transparent mirror is provided from the corner portion of the image display unit in an inclined manner (see, for example, Patent Document 2).
Since the “naked-eye type” device limits the view angle, the viewer is capable of viewing the stereoscopic image without wearing the glasses, which are required in the above “glasses type” device.